New AA SMD Woofer

[audioholic]

Correct.

But think about this. If you have a woofer with literally No BL (8-12tm at most) Super high Qts, but it plays 'flat'....and is linear

How much of the transient response are you loosing? The kick drums? How much is..delayed..or simply, not there?

It plays 'flat' anechoically? Again we need to define what we mean when we say it plays flat. Free-air in an anechoic environment? Or after its already been placed in an enclosure and in a car?

I dont think a lack of BL would be a big problem, so long as the BL remained consistent throughout the cone's excursion (defintion of BL optimization). Correct? The enclosure's dimensions can always be adjusted to account for such 'inadequacies'.

[na_rsx]

on a side note, i havent seen so many retards since the special olympics, and you tools know who you are. its takes a lot to go from 154 to 160, alot!!!

this sub looks insane, definitely looking forward to some meade videos with these bad boys, and those idiots that came off saying meade is an asshole because of his attitude is basially your fault. many started bashing him and calling names, then when he stepped in to defend himself, he was an asshole.

either waym good luck steve, hope to see some videos soon.

[Mc_Hammer]

holy cow how did people miss this post!!! very interesting indeed!!!

meh, that sub has been "around" for a while, it was put into production long before the patents were sold... im pretty sure everyone decided it was a tc5200 clone

[NDMstang65]

It plays 'flat' anechoically? Again we need to define what we mean when we say it plays flat. Free-air in an anechoic environment? Or after its already been placed in an enclosure and in a car?

I dont think a lack of BL would be a big problem, so long as the BL remained consistent throughout the cone's excursion (defintion of BL optimization). Correct? The enclosure's dimensions can always be adjusted to account for such 'inadequacies'.

Lack of BL is a huge problem..in regard to transient response.

If you are already sitting at a .7 Qts at rest...what happens when you get to say 70% of linear stroke? Your at a 1.x Qts and a BL of...1-2TM?

[audioholic]

Lack of BL is a huge problem..in regard to transient response.

If you are already sitting at a .7 Qts at rest...what happens when you get to say 70% of linear stroke? Your at a 1.x Qts and a BL of...1-2TM?

Well I agree a substantial lack of BL would be a problem. But I assumed we were talking within the realm of real world speakers. Who would build a subwoofer with such pitiful BL?

I think the old RE XXX is a good example of a sub that doesn't have alot of Bl, relatively speaking, but whose transient response was far from poor. While subs with greater BL (MT for example) did not necessarily have better transient response capabilities.

If the discussion is moving towards transient response now, we will again need to consider the speaker's suspension, and the enclosure it is housed in. There are certainly more factors than how much BL force the motor generates, or even how linear that BL force is throughout the speaker's stroke.

I know you know all this, just saying...

[NDMstang65]

Well I agree a substantial lack of BL would be a problem. But I assumed we were talking within the realm of real world speakers. Who would build a subwoofer with such pitiful BL?

I think the old RE XXX is a good example of a sub that doesn't have alot of Bl, relatively speaking, but whose transient response was far from poor. While subs with greater BL (MT for example) did not necessarily have better transient response capabilities.

If the discussion is moving towards transient response now, we will again need to consider the speaker's suspension, and the enclosure it is housed in. There are certainly more factors than how much BL force the motor generates, or even how linear that BL force is throughout the speaker's stroke.

I know you know all this, just saying...

Oh of course, i'm not pointing fingers at subs that lack there of...that's not the point of it...but most have characteristics of huge gaps, pole vents, inside of the motor hogged out, dead slugs purposely built into the motor that is uncharged and causes tons of issues. You will notice a more pronounced 'snappy' sound with a woofer that does not have a high Q...and plenty of force to back it up..

[Kyle_Keating]

Correct.

But think about this. If you have a woofer with literally No BL (8-12tm at most) Super high Qts, but it plays 'flat'....and is linear

How much of the transient response are you loosing? The kick drums? How much is..delayed..or simply, not there?

low or high BL has nothing to do with delaying anything.

[Kyle_Keating]

Lack of BL is a huge problem..in regard to transient response.

omg.....

[audioholic]

omg.....

Dont quote that out of context to misrepresent what he was saying. Not only did you leave out the following sentence which was an example of low BL to the extreme, you also left out the entire following post he made where he stipulated that he was "not pointing fingers at subs that lack there of".

[NDMstang65]

low or high BL has nothing to do with delaying anything.

No Grasshoppa.

Taking it out of context to make your argument is a fantastic way to win right? I'm using this as an example. So now let's get away from speakers and look at a real world application that just so happens to have the same correlation as BL and transient response.

1)A car, gasoline powered, has 20 foot pounds of torque and 100 horse power.

2)A car, with an electric motor, has 2 horse power, and 1000 pound feet of torque.

Which one will react/launch faster and harder? Which one will pull the non-drive wheels off of the ground? Which one will be at 1 foot first? 10 feet? 100 feet? (Hint; the answer is not number 1)

That, sir. Is a mechanical view of Transient response. I guess Thilo forgot to teach you that one didn't he?

[TheLow]

No Grasshoppa.

Taking it out of context to make your argument is a fantastic way to win right? I'm using this as an example. So now let's get away from speakers and look at a real world application that just so happens to have the same correlation as BL.

1)A car, gasoline powered, has 20 foot pounds of torque and 100 horse power.

2)A car, with an electric motor, has 2 horse power, and 1000 pound feet of torque.

Which one will launch faster and harder? Which one will pull the non-drive wheels off of the ground? (Hint; the answer is not number 1)

That, sir. Is a mechanical view of Transient response. I guess Thilo forgot to teach you that one didn't he?

the fan, shit did hit. ( shit has hit the fan )

[tc3k101]

the fan, shit did hit. ( shit has hit the fan )

x2 lol

[Warbleed]

flat BL does not mean flat frequency response, Flat BL means the cone will map correctly to the input voltage be it a simple sin wave or some complex harmonics from a musical instrument. Its also not about how much BL you have, its about how flat it is, or rather how relative it is. A non-flat BL curve will invoke the drivers own harmonics that may not necessarily be in the input signal. Not all harmonics sound good either. I agree tho, flat frequency response is not ideal for everyone, but your right, that has nothing to do with linear motors. The largest drawback to ALL linear motors is sensitivity, not their own linear BL product.

Uhm...this supports Nick's point?One of Nick's main points was that flat BL does not equate to flat response. The flattest BL curve in the world won't make a bit of difference if the entire moving assembly doesn't move in a linear fashion. It doesn't guarantee a flat Le curve (or a low initial Le), it doesn't guarantee a flat Cms curve either.

Flat BL curves don't make up for response peaks, which are often due to a sky high Qtc (because of a sky high Qes). You cannot simply make up for a lack of motorforce with more power, either.

A high Qts coupled with an extremely high Mms is never a good thing in terms of the frequency response you get from a speaker. You cannot sacrifice motor strength and moving mass to a large degree without consequences on sound and performance. The motor is certainly linear, but at what cost?

[Kyle_Keating]

Uhm...this supports Nick's point?One of Nick's main points was that flat BL does not equate to flat response. The flattest BL curve in the world won't make a bit of difference if the entire moving assembly doesn't move in a linear fashion. It doesn't guarantee a flat Le curve (or a low initial Le), it doesn't guarantee a flat Cms curve either.

Flat BL curves don't make up for response peaks, which are often due to a sky high Qtc (because of a sky high Qes). You cannot simply make up for a lack of motorforce with more power, either.

A high Qts coupled with an extremely high Mms is never a good thing in terms of the frequency response you get from a speaker. You cannot sacrifice motor strength and moving mass to a large degree without consequences on sound and performance. The motor is certainly linear, but at what cost?

ok, we're all on the same page, now someone go make some speakers!

[DevilDriver]

I have been meaning to reply in this thread, but haven't had the time, or desire really, to do so. Obviously clarification is required here.

No, it's not a matter of not liking linearity, linearity is a great thing. I don't like the idea of having to use huge gaps and a huge motor to get any sort of a decent bl or motor force out of it...(wasting materials, adding cost, generally a sub-par ideology)

If things aren't glued down, the gap has to be wider...if the coil changes density in the gap...the gap..has to be wider. (again...wasting materials, adding cost, for being able to screw a basket on and off..is not worth it)

If you can have a +/- 3dBa response from 20-90Hz in a given scenario without using 'linear motor technology' or 'xbl^2' then why wouldn't you? You get the end result that you want, which is no equalization and it plays flat..and you don't have to pay for rights of technology that is patented?

Essentially this is an argument of price vs performance. There is no way anyone can possibly argue that.

What's more important..to say that something is 100% linear on a piece of paper but on the contrary sounds horrid, or something that sounds great..doesn't need EQ'ing...and is..98% linear through the entire stroke?

Then we get into the argument of..well wait a second. What if it is the general norm of psycho-acoustics for liking peaks..liking valleys..liking distortion? Liking true LIVE music? You can put 10 different people in a room and it will be 10 different ways of perception...you'll have "sq" guys who think flat is god. You'll have horn loaded compression drivers that many think sound amazing...

If something is 100% linear on paper (and with even response) but sounds horrible, then it is the fault of the material...the music. By the way, that paper is real life, too, just so you know. Either way, I want music that sounds great, and a system that plays music (but nothing else).

Sad thing is..the vast majority of people, including myself, can't stand the sound of something that is 100% flat..it sounds dead to me, and I don't like it...

What is is about "100% flat" that you don't like? Keep in mind you have only described one characteristic of the sound's physical properties (ie. it's axial response). Also, I don't know if this is reference to the sound at the ear or measured 1m away from a driver.

So i can flop a piece of material, 100% linear, down to the micron for arguments sake.

It plays the recording accurately just and only just because it is linear and therefore an accurate reproduction of the recording? What happens when the motor peaks at 58Hz? It's still linear...but you've got a 3.9dBa peak at 58Hz? Is that because of the recording? Or is that because of the motor getting happy? (Keep in mind it is still linear)

It's not the linearity of something that matters, it's well can it play flat or not? If it plays flat from 0-20Khz then...it's linear? Or is it..un-linear? Is it the recording? Or is it the speaker?

It is important that a driver is both linear and has even response on all axis'. Further, even response is more achievable with less distortion, which is achieved with engineering that specifically targets linearity in Bl, Cms, and Le (with coil position and power, for those relevant).

It simply boils down to are you listening to the woofer paper that says it has a flat BL curve, and assuming that it yields a 100% Linear and +/- 1dB response?

Having re-read the thread, at no point did I say there is a direct correlation between BL linearity and flat axial response. I did say that there is a correlation between low HD and IMD with flat axial response; since improved BL linearity often results in decreased HD and IMD, there is a function that relates BL linearity with frequency response, but it is grossly more complex than that. Aside from the HD and IMD created by BL, Cms, and Le non-linearities, you will experience variations in response related to the alignment, the cone and surround geometry, the thermal properties of all materials, and the environment.

What the thread eventually boiled down to is another bizarre argument of "real world vs science" as if the science we are talking about does not occur in the real world. The "real world" people are aware of a handful of the things that a driver is judged with scientifically, and thus feel it necessary to deride scientific design and interpretation (or engineering, if you will) by simplifying it to "looking at BL curves on a paper". So to make sure that the usual crowd does not once again take this out of context:

1) When evaluating a driver, even response on all axis' with no distortion is preferable. The presence of distortion makes even response less likely.
2) Distortion (THD and IMD) is generated by non-linearities in BL, Cms, and Le vs coil position and current.
3) Engineering with limited distortion in mind can improve response and lower distortion. As such, any approach that targets causes of distortion should be valued.

Note: When I refer to "even response on all axis'", what I am trying to convey is even response on axis, and good polar response as well.